[wbarmy]

The scientists used the DNA of the various spider species to reconstruct the history of how they evolved. They showed that the dark spiders and the white spiders have repeatedly evolved from ancestral gold spiders, six times in the case of the dark spiders and twice in the case of the white ones.

This is just as bad as climate science. The scientists make the assumption that the stick spiders evolved from the gold spiders, then postulate how often there would have to mutations to get from the gold spider to the stick spider. This gives them a time frame, and viola, they have proof of evolution.

But they still have no proof that the stick came from the gold. Jut like Darwin's finches, they are still finches, and if stuck in the same cage with the others, they will breed. They are not different species, the DNA did not change, they still have the same number of chromosomes.

[exDemMom]

Actually, it is a fairly straightforward process to construct a phylogenetic tree and determine what traits the original population had, and traits of descendent populations. The process works so well that you do not even need to know which DNA sequences come from the parent population. Once you run the analysis, you know exactly which sequence came from the original, and the order in which the child populations emerged.

The techniques of evolutionary biology are used a lot, in many contexts.